The American Cryptogram Association (ACA) is a nonprofit volunteer organization devoted to disseminating cryptographic knowledge. Members make up and solve their own creations strictly for the fun of it. Every two months, the ACA journal, The Cryptogram, publishes about 100 ciphers, as well as articles on practical cryptanalysis, the history of the ACA, and book reviews. From the sample issue, learn about various cipher systems and try sample puzzles: key word alphabets, Caesar alphabets and Caesar tips, aristocrats, patristocrats, cryptarithms (mathematical problems in cipher, where the letters represent numbers), xenocrypts, and cipher exchanges. Also, read the "ACA and You" booklet, which covers jargon and standards for ciphers; see images of cipher machines; find computer supplements and program listings from the ACA Computer Column; download ciphers; learn about the Classical Crypto Books service, for the procurement of new (unused) books on traditional codes, ciphers, and signals intelligence at discount prices; obtain subscription information.